OBJECTIVE: Transrectal ultrasound (TRUS) has been widely used for guiding prostate implants, but not much for interstitial brachytherapy (IBT) of cervix cancer. The aim of our study is to report our experience with TRUS guided high dose rate (HDR) IBT in patients with carcinoma of uterine cervix. METHODS: During the year 2005-2006, 25 patients of cervical cancer not suitable for intracavitary radiotherapy (ICRT), were enrolled in this prospective study. We used B-K Medical USG machine (Falcon 2101) equipped with a TRUS probe (8658) having a transducer of 7.5 MHz for IBT. Post procedure, a CT scan was done for verification of needle position and treatment planning. Two weekly sessions of HDR IBT of 8-10 Gy each were given after pelvic external beam radiation therapy. RESULTS: A total of 40 IBT procedures were performed in 25 patients. Average duration of implant procedure was 50 minutes. There was no uterine perforation in any of 11 patients in whom central tandem was used. CT scan did not show needle perforation of bladder/rectum in any of the patients. During perioperative period, only 1 procedure (2.5%) was associated with hematuria which stopped within 6 hours. Severe late toxicity was observed in 3 (12%) patients. Overall pelvic control rate was 64%. CONCLUSION: Our experience suggests that TRUS is a practical and effective imaging device for guiding the IBT procedure of cervical cancer patients. It helps in accurate placements of needles thus avoiding the injury to normal pelvic structures.
Brachytherapy ; Cervix Uteri ; Female ; Hematuria ; Humans ; Needles ; Perioperative Period ; Prospective Studies ; Prostate ; Transducers ; Uterine Cervical Neoplasms ; Uterine Perforation

PURPOSE: The aim is to study the dependence of deformable based auto-segmentation of head and neck organs-at-risks (OAR) on anatomy matching for a single atlas based system and generate an acceptable set of contours. METHODS: A sample of ten patients in neutral neck position and three atlas sets consisting of ten patients each in different head and neck positions were utilized to generate three scenarios representing poor, average and perfect anatomy matching respectively and auto-segmentation was carried out for each scenario. Brainstem, larynx, mandible, cervical oesophagus, oral cavity, pharyngeal muscles, parotids, spinal cord, and trachea were the structures selected for the study. Automatic and oncologist reference contours were compared using the dice similarity index (DSI), Hausdroff distance and variation in the centre of mass (COM). RESULTS: The mean DSI scores for brainstem was good irrespective of the anatomy matching scenarios. The scores for mandible, oral cavity, larynx, parotids, spinal cord, and trachea were unacceptable with poor matching but improved with enhanced bony matching whereas cervical oesophagus and pharyngeal muscles had less than acceptable scores for even perfect matching scenario. HD value and variation in COM decreased with better matching for all the structures. CONCLUSION: Improved anatomy matching resulted in better segmentation. At least a similar setup can help generate an acceptable set of automatic contours in systems employing single atlas method. Automatic contours from average matching scenario were acceptable for most structures. Importance should be given to head and neck position during atlas generation for a single atlas based system.
Brain Stem ; Head and Neck Neoplasms ; Head ; Humans ; Larynx ; Mandible ; Methods ; Mouth ; Neck ; Organs at Risk ; Pharyngeal Muscles ; Radiotherapy ; Spinal Cord ; Trachea